1. Field of the invention
This invention is directed to an ultra-wideband man-portable radio antenna that operates in the 30 MHz to 500 MHz frequency range using a single antenna.
2. Description of the Prior Art
Most man-portable communications antennas are of the monopole type. A typical monopole antenna uses a metal wire, a thin surface-metalized rod, or a thin, narrow metal tape and operates against the radio enclosure. Although a monopole antenna is simple and inexpensive to manufacture, it has the following serious deficiencies:
1. Typical wire/rod/tape monopole antennas exhibit a narrow instantaneous bandwidth, on the order of one magnitude lower than the bandwidth of the vest antenna according to the present invention.
2. A monopole has a characteristic visual signature (extending above the operator""s head) thus identifying the radio operator and disclosing the operator""s location
3. Monopole antennas are vulnerable to entanglement in foliage and damage in urban environments.
4. To prevent the deficiencies listed above, many monopole antennas are deployed on a xe2x80x9cneed to usexe2x80x9d basis meaning that they have to be assembled/set up (unfurled in case of metal tape or assembled out of several sections in case of metalized rods) prior to use and then disassembled for stowage after use, which increases the operator workload and precludes instantaneous establishment of radio communication at any arbitrary instant in time.
5. Multiple monopoles (a monopole set) is required to cover the frequency range of 30 MHz to 500 MHz, increasing the number of items/weight the soldier has to carry and restricting the radio operation to only one frequency band at a time (the one corresponding to the particular monopole selected as the antenna).
6. To reduce the monopole length and/or avoid the use of multiple monopoles for man-portable radios, an antenna tuner is used in conjunction with the monopole to increase the monopole""s operational bandwidth but this limits the use of the radio to a xe2x80x9csingle channelxe2x80x9d (narrowband) operation at a time.
The vest antenna according to the present invention overcomes the foregoing and other deficiencies of the prior art by providing a unique combination that no conventional man-portable antenna has been able to provide. The present invention provides a new approach to man-portable antennas by fully integrating the antenna with the combat wear of a soldier. The vest antenna according to the present invention enables radio operation over a very wide frequency range using an ultra-wideband antenna worn by the radio operator.
It is an object of the invention to provide a man-portable antenna that provides wideband operation capability to provide efficient operation in the entire 30 MHz to 500 MHz frequency range without an antenna tuner.
Another object of the invention is to provide a man-portable antenna that is non-obtrusive and that exhibits no visual signature.
It is an object of the invention to provide a man-portable antenna that is inexpensive to manufacture, operate, and maintain and that adds minimal weight to operator.
Still another object of the invention is to provide a man-portable antenna that provides safety from possible entanglements in high voltage overhead wires;
A further object of the invention is to provide a man-portable antenna that is wearable by the operator through integration with existing items of clothing;
Yet another object of the invention is to provide a man-portable antenna that is formed using existing combat equipment such as a flak vest or a load bearing vest that is used as a base for conducting cloth.
An object of the invention is to provide a man-portable antenna that has extensive application potential for both military and non-military uses.
An object of the invention is to provide a man-portable antenna that has a nearly omni-directional radiation pattern with vertical polarization.
Another object of the invention is to provide a man-portable antenna that requires no set-up for its usage and that is suitable for all-weather antenna operation.
Accordingly, in accordance with the present invention, a man-portable antenna assembly formed on a vest to be worn as an article of clothing comprises first and second electrically conducting portions connected to the vest. A non-conducting band is formed on the vest between the first and second electrically conducting portions. A first conducting strip is arranged in a first portion of the vest to provide an electrical connection between the first and second electrically conducting portions. A second conducting strip is placed in a second portion of the vest and connected to the first electrically conducting portion. A conducting patch is connected to the second electrically conducting portion, and a feed conductor is electrically connected to the conducting patch.
The first and second electrically conducting portions the vest preferably comprise metalized cloth arranged to substantially cover all of the vest except for the non-conducting band.
The first conducting strip preferably extends the full length of the front portion of the vest.
The feed conductor preferably comprises a coaxial cable having its center conductor connected to the conducting patch.
The second conducting strip and the conducting patch preferably are on a back portion of the vest and are separated by the non-conducting band.
The second conducting strip preferably extends between a lower edge portion of the vest and the non-conducting band and the coaxial cable has a shield that preferably is secured to the second conducting strip.
The non-conducting band preferably divides the vest so that the first and second conducting portions have substantially equal areas.
The non-conducting band preferably is formed to have a substantially uniform width of about 2.5 cm.